Overview

Whooping cough (pertussis) is a highly contagious respiratory tract infection. In many people, it's marked by a severe hacking cough followed by a high-pitched intake of breath that sounds like "whoop."

Before the vaccine was developed, whooping cough was considered a childhood disease. Now whooping cough primarily affects children too young to have completed the full course of vaccinations and teenagers and adults whose immunity has faded.

Deaths associated with whooping cough are rare but most commonly occur in infants. That's why it's so important for pregnant women — and other people who will have close contact with an infant — to be vaccinated against whooping cough.

Symptoms

Once you become infected with whooping cough, it takes about seven to 10 days for signs and symptoms to appear, though it can sometimes take longer. They're usually mild at first and resemble those of a common cold:

Causes

Whooping cough is caused by bacteria. When an infected person coughs or sneezes, tiny germ-laden droplets are sprayed into the air and breathed into the lungs of anyone who happens to be nearby.

Risk factors

Whooping cough is thought to be on the rise for two main reasons. The whooping cough vaccine you receive as a child eventually wears off. This leaves most teenagers and adults susceptible to the infection during an outbreak — and there continue to be regular outbreaks.

In addition, children aren't fully immune to whooping cough until they've received at least three shots, leaving those 6 months and younger at greatest risk of contracting the infection.

Complications

Teens and adults often recover from whooping cough with no problems. When complications occur, they tend to be side effects of the strenuous coughing, such as:

Bruised or cracked ribs

Abdominal hernias

Broken blood vessels in the skin or the whites of your eyes

Infants

In infants — especially those under 6 months of age — complications from whooping cough are more severe and may include:

Pneumonia

Slowed or stopped breathing

Dehydration or weight loss due to feeding difficulties

Seizures

Brain damage

Because infants and toddlers are at greatest risk of complications from whooping cough, they're more likely to need treatment in a hospital. Complications can be life-threatening for infants younger than 6 months old.

Prevention

The best way to prevent whooping cough is with the pertussis vaccine, which doctors often give in combination with vaccines against two other serious diseases — diphtheria and tetanus. Doctors recommend beginning vaccination during infancy.

The vaccine consists of a series of five injections, typically given to children at these ages:

2 months

4 months

6 months

15 to 18 months

4 to 6 years

Vaccine side effects

Side effects of the vaccine are usually mild and may include fever, crankiness, headache, fatigue or soreness at the site of the injection.

Booster shots

Adolescents. Because immunity from the pertussis vaccine tends to wane by age 11, doctors recommend a booster shot at that age to protect against whooping cough (pertussis), diphtheria and tetanus.

Adults. Some varieties of the every-10-year tetanus and diphtheria vaccine also include protection against whooping cough (pertussis). This vaccine will also reduce the risk of your transmitting whooping cough to infants.

Pregnant women. Health experts now recommend that pregnant women receive the pertussis vaccine between 27 and 36 weeks of gestation. This may also give some protection to the infant during the first few months of life.

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